Method for the production of alicyclic polycarboxylic acid esters from partial esters of aromatic polycarboxylic acids
View Patent ↗The invention relates to a process for preparing full esters of alicyclic polycarboxylic acids from partial esters of aromatic polycarboxylic acids by hydrogenation of the partial ester followed by esterification of this compound.
1. A process for preparing cycloaliphatic polycarboxylic esters, which comprises:
a) hydrogenating a partial ester of the corresponding aromatic polycarboxylic acid or of the corresponding aromatic polycarboxylic anhydride whose carboxylic acid or anhydride groups have been partially esterified with at least one branched or unbranched alkyl, cycloalkyl, and/or alkoxyalkyl alcohol having from 3 to 15 carbon atoms, and
b) reacting the resultant cycloaliphatic partial ester with at least one branched or unbranched alkyl, cycloalkyl, and/or alkoxyalkyl alcohol having from 3 to 15 carbon atoms in the presence of a titanium or zirconium catalyst to give a full ester product.
2. The process as claimed in claim 1 , wherein
the hydrogenation of the aromatic partial ester is carried out with a catalyst comprising at least one metal of the 8 th transition group of the periodic table.
3. The process as claimed in claim 1 , wherein
the alcohol or alcohol mixture reacted with the cycloaliphatic partial ester is the same as that which would be obtained by saponifying the partial ester of the aromatic polycarboxylic acid.
4. The process as claimed in claim 1 , wherein
the alcohol or alcohol mixture reacted with the cycloaliphatic partial ester is other than that which would be obtained by saponifying the partial ester of the aromatic polycarboxylic acid.
5. The process as claimed in claim 1 , wherein the aromatic polycarboxylic acid or the corresponding polycarboxylic anhydride comprises 2, 3 or 4 carboxyl functional groups.
6. The process as claimed in claim 1 , wherein the aromatic polycarboxylic acid or the corresponding polycarboxylic anhydride is comprised of one benzene ring or from 2 to 5 condensed benzene rings.
7. The process as claimed in claim 1 , wherein the alcohol comprises branched or unbranched alkyl, cycloalkyl, and/or alkoxyalkyl groups having from 8 to 13 carbon atoms.
8. The process as claimed in claim 1 , wherein the partial ester is a partial ester of an aromatic polycarboxylic acid and comprises a monoester of a benzene-1,2-, 1,3-, or 1,4-dicarboxylic acid.
9. The process as claimed in claim 1 , wherein the partial ester is a partial ester of an aromatic polycarboxylic acid and is a mono- or diester of 1,2,3-, 1,2-4- or 1,3,5-trimellitic acid.
10. The process as claimed in claim 2 , wherein the alcohol or alcohol mixture reacted with the cycloaliphatic partial ester is the same as that which would be obtained by saponifying the partial ester of the aromatic polycarboxylic acid.
11. The process as claimed in claim 2 , wherein the alcohol or alcohol mixture reacted with the cycloaliphatic partial ester is other than that which would be obtained by saponifying the partial ester of the aromatic polycarboxylic acid.
12. The process as claimed in claim 1 , wherein the alcohol component of the cycloaliphatic partial ester is a C 8 or C 9 aliphatic alcohol or isomer mixture of these alcohols and alcohol reactant of step (b) is a C 8 or C 9 aliphatic alcohol or isomer mixture of these alcohols.